[dpdk-dev] [PATCH v3] fm10k: fix switch manager high CPU usage

[Chen, Jing D]

Hi,

Best Regards,
Mark


> -----Original Message-----
> From: He, Shaopeng
> Sent: Friday, February 05, 2016 10:46 AM
> To: dev at dpdk.org
> Cc: Chen, Jing D; Wang, Xiao W; He, Shaopeng
> Subject: [PATCH v3] fm10k: fix switch manager high CPU usage
> 
> fm10k switch core uses source MAC + VID + SGLORT to do
> look up in MAC table. If no match, an exception interrupt
> will be sent to the switch manager. Too much of this kind
> of exception interrupts cause switch manager side high CPU
> usage.
> To reproduce this issue, one DPDK testpmd runs on a server
> with one fm10k NIC, mac forwards test traffic from one of
> fm10k ports to another port. The CPU usage for the switch
> manager will go up to about 20% for test traffic rate at
> 10G bps, comparing to near 0% for no test traffic.
> This patch fixes this issue. A default SGLORT is assigned
> to each TX queue. This default value works for non-VMDq mode
> and current VMDq example. For advanced VMDq usage, e.g.
> different source MAC address for different TX queue, FTAG
> forwarding function could be used to change this default
> SGLORT value.
> 
> Fixes: 9ae6068c ("fm10k: add dev start/stop")
> 
> Signed-off-by: Shaopeng He <shaopeng.he at intel.com>
Acked-by : Jing Chen <jing.d.chen at intel.com>